Prospective histopathologic evaluation of lifestyle modification in nonalcoholic fatty liver disease: a randomized trial

Improvement in histological endpoints of MAFLD following a 12-week aerobic exercise intervention

BACKGROUND

Lifestyle interventions are the primary treatment for metabolic (dysfunction) associated fatty liver disease (MAFLD). However, the histological and cardiometabolic effects of aerobic exercise in MAFLD remain unclear.

AIMS

To assess the effects of a 12-week aerobic exercise intervention on histological and cardiometabolic endpoints in MAFLD.

METHODS

Patients with biopsy-confirmed MAFLD participated in a 12-week aerobic exercise intervention. Liver histology, cardiorespiratory fitness (estimated V̇O_2max ), physical activity, anthropometry and biochemical markers were assessed at baseline, intervention completion, and 12 and 52 weeks after intervention completion.

RESULTS

Twenty-four patients completed the exercise intervention (exercise group n = 16, control group n = 8). In the exercise group, 12 weeks of aerobic exercise reduced fibrosis and hepatocyte ballooning by one stage in 58% (P = 0.034) and 67% (P = 0.020) of patients, with no changes in steatosis (P = 1.000), lobular inflammation (P = 0.739) or NAFLD activity score (P = 0.172). Estimated V̇O_2max increased by 17% compared to the control group (P = 0.027) but this level of improvement was not maintained at 12 or 52 weeks after the intervention. Patients with fibrosis and ballooning improvement increased estimated V̇O_2max by 25% (P = 0.020) and 26% (P = 0.010), respectively. Anthropometric reductions including body mass (P = 0.038), waist circumference (P = 0.015) and fat mass (P = 0.007) were also observed, but no patient achieved 7%-10% weight loss.

CONCLUSION

This study highlights the potential benefits of a 12-week aerobic exercise intervention in improving histological endpoints of MAFLD. The development of strategies to ensure continued engagement in aerobic exercise in MAFLD are needed.

The Gut Microbiota and Its Metabolites, Novel Targets for Treating and Preventing Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is one of the most prevalent metabolic disorders worldwide, along with obesity and type 2 diabetes. NAFLD involves a series of liver abnormalities from simple hepatic steatosis to non-alcoholic steatohepatitis, which can ultimately lead to liver cirrhosis and cancer. The gut-liver axis plays an important role in the development of NAFLD, which depends mainly on regulation of the gut microbiota and its bacterial products. These intestinal bacterial species and their metabolites, including bile acids, tryptophan catabolites, and branched-chain amino acids, regulate adipose tissue and intestinal homeostasis and contribute to the pathogenesis of NAFLD/non-alcoholic steatohepatitis. In this review, the current evidence regarding the key role of the gut microbiota and its metabolites in the pathogenesis and development of NAFLD is highlighted, and the advances in the progression and applied prospects of gut microbiota-targeted dietary and exercise therapies is also discussed.

Kupffer Cells in Non-alcoholic Fatty Liver Disease: Friend or Foe?

The prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing all around the world and it may become the primary cause of terminal liver disease in adults and children in the next few decades. However, the pathogenesis of NAFLD is complex, and the Food and Drug Administration (FDA) has not approved any drugs for its treatment. Kupffer cells are the key cells regulating immunity in the liver, and the effect of their unique polarization on NAFLD has received increasing attention. Kupffer cells mainly reside in the lumen of hepatic sinusoids and account for 80% to 90% of colonized macrophages in the human body. They are phagocytic cells with the capacity for self-renewal that rarely migrate from their niche in the liver, and play a crucial role in regulating and maintaining homeostasis. Upon liver damage, Kupffer cells will be activated, releasing a good deal of inflammatory cytokines and chemokines. This review summarizes the multiple roles of Kupffer cells in the pathogenesis of NAFLD, the role of infiltrating macrophages in the pathogenesis of NAFLD is also briefly discussed, and aims to provide a theoretical basis for designing an NAFLD treatment strategy with Kupffer cells as the therapeutic target.

Effects of total fat intake on body fatness in adults

BACKGROUND

The ideal proportion of energy from fat in our food and its relation to body weight is not clear. In order to prevent overweight and obesity in the general population, we need to understand the relationship between the proportion of energy from fat and resulting weight and body fatness in the general population.

OBJECTIVES

To assess the effects of proportion of energy intake from fat on measures of body fatness (including body weight, waist circumference, percentage body fat and body mass index) in people not aiming to lose weight, using all appropriate randomised controlled trials (RCTs) of at least six months duration.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, Clinicaltrials.gov and the WHO International Clinical Trials Registry Platform (ICTRP) to October 2019. We did not limit the search by language.

SELECTION CRITERIA

Trials fulfilled the following criteria: 1) randomised intervention trial, 2) included adults aged at least 18 years, 3) randomised to a lower fat versus higher fat diet, without the intention to reduce weight in any participants, 4) not multifactorial and 5) assessed a measure of weight or body fatness after at least six months. We duplicated inclusion decisions and resolved disagreement by discussion or referral to a third party.

DATA COLLECTION AND ANALYSIS

We extracted data on the population, intervention, control and outcome measures in duplicate. We extracted measures of body fatness (body weight, BMI, percentage body fat and waist circumference) independently in duplicate at all available time points. We performed random-effects meta-analyses, meta-regression, subgrouping, sensitivity, funnel plot analyses and GRADE assessment.

MAIN RESULTS

We included 37 RCTs (57,079 participants). There is consistent high-quality evidence from RCTs that reducing total fat intake results in small reductions in body fatness; this was seen in almost all included studies and was highly resistant to sensitivity analyses (GRADE high-consistency evidence, not downgraded). The effect of eating less fat (compared with higher fat intake) is a mean body weight reduction of 1.4 kg (95% confidence interval (CI) -1.7 to -1.1 kg, in 53,875 participants from 26 RCTs, I² = 75%). The heterogeneity was explained in subgrouping and meta-regression. These suggested that greater weight loss results from greater fat reductions in people with lower fat intake at baseline, and people with higher body mass index (BMI) at baseline. The size of the effect on weight does not alter over time and is mirrored by reductions in BMI (MD -0.5 kg/m², 95% CI -0.6 to -0.3, 46,539 participants in 14 trials, I² = 21%), waist circumference (MD -0.5 cm, 95% CI -0.7 to -0.2, 16,620 participants in 3 trials; I² = 21%), and percentage body fat (MD -0.3% body fat, 95% CI -0.6 to 0.00, P = 0.05, in 2350 participants in 2 trials; I² = 0%). There was no suggestion of harms associated with low fat diets that might mitigate any benefits on body fatness. The reduction in body weight was reflected in small reductions in LDL (-0.13 mmol/L, 95% CI -0.21 to -0.05), and total cholesterol (-0.23 mmol/L, 95% CI -0.32 to -0.14), with little or no effect on HDL cholesterol (-0.02 mmol/L, 95% CI -0.03 to 0.00), triglycerides (0.01 mmol/L, 95% CI -0.05 to 0.07), systolic (-0.75 mmHg, 95% CI -1.42 to -0.07) or diastolic blood pressure(-0.52 mmHg, 95% CI -0.95 to -0.09), all GRADE high-consistency evidence or quality of life (0.04, 95% CI 0.01 to 0.07, on a scale of 0 to 10, GRADE low-consistency evidence).

AUTHORS' CONCLUSIONS

Trials where participants were randomised to a lower fat intake versus a higher fat intake, but with no intention to reduce weight, showed a consistent, stable but small effect of low fat intake on body fatness: slightly lower weight, BMI, waist circumference and percentage body fat compared with higher fat arms. Greater fat reduction, lower baseline fat intake and higher baseline BMI were all associated with greater reductions in weight. There was no evidence of harm to serum lipids, blood pressure or quality of life, but rather of small benefits or no effect.

Exercise Attenuates the Transition from Fatty Liver to Steatohepatitis and Reduces Tumor Formation in Mice

Non-alcoholic fatty liver disease (NAFLD) leads to steatohepatitis (NASH), fibrosis, and hepatocellular carcinoma. For sedentary patients, lifestyle interventions combining exercise and dietary changes are a cornerstone of treatment. However, the benefit of exercise alone when dietary changes have failed is uncertain. We query whether exercise alone arrests the progression of NASH and tumorigenesis in a choline-deficient, high-fat diet (CD-HFD) murine model. Male C57Bl/6N mice received a control diet or CD-HFD for 12 weeks. CD-HFD mice were randomized further for 8 weeks of sedentariness (SED) or treadmill exercise (EXE). CD-HFD for 12 weeks produced NAFL. After 20 weeks, SED mice developed NASH and hepatic adenomas. Exercise attenuated the progression to NASH. EXE livers showed lower triglycerides and tumor necrosis factor-α expression, less fibrosis, less ballooning, and a lower NAFLD activity score than did SED livers. Plasma transaminases and triglycerides were lower. Exercise activated AMP-activated protein kinase (AMPK) with inhibition of mTORC1 and decreased S6 phosphorylation, reducing hepatocellular adenoma. Exercise activated autophagy with increased LC3-II/LC3-I and mitochondrial recruitment of phosphorylated PTEN-induced kinase. Therefore, exercise attenuates the transition from NAFL to NASH, improves biochemical and histological parameters of NAFLD, and impedes the progression of fibrosis and tumorigenesis associated with enhanced activation of AMPK signaling and favors liver autophagy. Our work supports the benefits of exercise independently of dietary changes.

Obeticholic acid for the treatment of nonalcoholic steatohepatitis

INTRODUCTION

NAFLD has grown to become the most prevalent liver disease in the world, with a quarter of the general population estimated to have the disease. NASH, characterized as NAFLD with inflammation, is associated with worsening fibrosis along with increased incidence of HCC. Despite high prevalence of this disease, no pharmacologic treatments approved by regulatory agencies are available.

AREAS COVERED

This review briefly discusses present understanding of NASH pathology and currently available treatments. We also discuss data on the role of OCA as an FXR agonist in modulating disease in NASH. A comprehensive literature search of review articles, original research articles, and prospective clinical trials from 1998 to the present was performed.

EXPERT OPINION

Based on 18-month interim findings of the REGENERATE trial, OCA likely improves fibrosis in NASH and therefore may have a beneficial effect in delaying or even preventing cirrhosis. The side effect of an atherogenic lipoprotein profile may adversely affect long-term outcomes, though studies have shown that co-administration of statins is able to mitigate this effect. OCA is likely to become an option for treatment, but the specific context within which it may be prescribed still needs to be clarified.

Effect of lifestyle modification education based on health belief model in overweight/obese patients with non-alcoholic fatty liver disease: A parallel randomized controlled clinical trial

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is the most common emerging liver disease worldwide. Lifestyle modification is the most emphasized method on management of this disease.

METHODS

In order to conduct this parallel, randomized controlled trial study, eighty-two NAFLD patients recruited and allocated to intervention group or the control.

RESULTS

After two months of intervention, significant improvements in all health belief model (HBM) variables and knowledge were seen within the intervention group (p < 0.001) and also the improvements were significantly superior between two groups (p < 0.001). Furthermore, prominent significant reduction for liver enzyme was observed in the intervention group compared to the controls. Similarly, ultra-sonographic findings revealed a significant improvement in the intervention group versus control.

CONCLUSIONS

This HBM-based lifestyle modification education could be effective not only in the HBM domains but also in the improvement of NAFLD parameters. Therefore, it could be useful to use this educational program for NAFLD patients in order to impact on their beliefs and body together.

REGISTRATION

Iranian Registry of Clinical Trials (IRCT2014101811763N17).

Managing NAFLD in Type 2 Diabetes: The Effect of Lifestyle Interventions, a Narrative Review

The prevalence of non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes (T2D) is increasing. As a strong association between these two diseases exist, it is unsurprising that the number of patients with coexisting NAFLD and T2D is also increasing. These patients display a deleterious metabolic profile (e.g. hypertriglyceridemia), and increased mortality rates relative to those with only NAFLD or T2D in isolation; therefore, effective treatment strategies are required. Here we review the available intervention studies that have investigated the effects of changes in lifestyle (diet and exercise/physical activity) on NAFLD in patients with both NAFLD and T2D. On the basis of the available evidence, it appears that the addition of any kind of exercise (i.e. resistance, aerobic, or high-intensity intermittent exercise) is beneficial for patients with both NAFLD and T2D. These effects appear to occur independently of changes in body weight. Hypocaloric diets leading to weight loss are also effective in improving metabolic parameters in patients with both NAFLD and T2D, with data indicating that ~ 7–10% weight loss is required in order to observe beneficial effects. It is unclear if multidisciplinary interventions incorporating changes in both diet and physical activity levels are a more effective treatment strategy in this population than diet or exercise interventions in isolation. In conclusion, it is clear that lifestyle interventions are an effective treatment strategy in patients with both NAFLD and T2D, although further research is required to optimise these interventions and determine their scalability.

Nutrition and Nonalcoholic Fatty Liver Disease: Current Perspectives

Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis are diseases in their own right as well as modifiable risk factors for cardiovascular disease and type 2 diabetes. With expanding knowledge on NAFLD pathogenesis, insights have been gleaned into molecular targets for pharmacologic and nonpharmacologic approaches. Lifestyle modifications constitute a cornerstone of NAFLD management. This article reviews roles of key dietary macronutrients and micronutrients in NAFLD pathogenesis and their effects on molecular targets shared with established or emerging pharmacotherapies. Based on current evidence, a recommendation for a dietary framework as part of the comprehensive management strategy for NAFLD is provided.

Evolution of NAFLD and Its Management

The global prevalence of nonalcoholic fatty liver disease (NAFLD) is estimated to be 25% and continues to rise worldwide in the setting of the obesity epidemic. This increase is especially concerning because NAFLD is often a progressive disease that can be associated with significant complications such as liver cirrhosis, hepatocellular carcinoma, and an increase in liver-related and overall mortality. Because of the devastating complications and comorbidities, NAFLD is a very costly disease for the healthcare system, with estimated annual direct medical costs exceeding $100 billion in the United States alone. Given this progressive course, it is imperative to make the diagnosis in patients with risk factors (metabolic syndrome, weight gain, and insulin resistance/diabetes). Once the diagnosis is made, the focus should shift to treatment and monitoring for the development of associated complications. Given that currently no pharmaceutical intervention is approved for the treatment of NAFLD, focus shifts instead to mitigation of risk factors through avoidance of foods that are rich in red meat, trans fats, refined carbohydrates, and high-fructose corn syrup; are low fiber; and have high energy density. The landmark of treatment, however, continues to be weight loss and improvement of insulin resistance, often through a multimodality approach. The current manuscript reviews the clinical phenotypes of NAFLD, its risk factors, and pathogenesis, as well as treatment options including lifestyle modifications and dietary interventions, medical therapies, endoscopic bariatric interventions, and bariatric surgery.

High Protein Diet and Metabolic Plasticity in Non-Alcoholic Fatty Liver Disease: Myths and Truths

Non-alcoholic fatty liver disease (NAFLD) is characterized by lipid accumulation within the liver affecting 1 in 4 people worldwide. As the new silent killer of the twenty-first century, NAFLD impacts on both the request and the availability of new liver donors. The liver is the first line of defense against endogenous and exogenous metabolites and toxins. It also retains the ability to switch between different metabolic pathways according to food type and availability. This ability becomes a disadvantage in obesogenic societies where most people choose a diet based on fats and carbohydrates while ignoring vitamins and fiber. The chronic exposure to fats and carbohydrates induces dramatic changes in the liver zonation and triggers the development of insulin resistance. Common believes on NAFLD and different diets are based either on epidemiological studies, or meta-analysis, which are not controlled evidences; in most of the cases, they are biased on test-subject type and their lifestyles. The highest success in reverting NAFLD can be attributed to diets based on high protein instead of carbohydrates. In this review, we discuss the impact of NAFLD on body metabolic plasticity. We also present a detailed analysis of the most recent studies that evaluate high-protein diets in NAFLD with a special focus on the liver and the skeletal muscle protein metabolisms.

Lifestyle modification in NAFLD/NASH: Facts and figures

The development of non-alcoholic fatty liver disease is closely linked to lifestyle factors, namely excessive caloric intake coupled with reduced physical activity and exercise. This review aims to examine the evidence behind lifestyle change as a tool to improve hepatic steatosis and liver histology in patients with non-alcoholic fatty liver disease/non-alcoholic steatohepatitis. Furthermore, potential barriers to adopting lifestyle changes and strategies to overcome these barriers in the clinical setting are discussed.

Association of Weight Loss Interventions With Changes in Biomarkers of Nonalcoholic Fatty Liver Disease: A Systematic Review and Meta-analysis

IMPORTANCE

Nonalcoholic fatty liver disease (NAFLD) affects about 25% of adults worldwide and is associated with obesity. Weight loss may improve biomarkers of liver disease, but its implications have not been systematically reviewed and quantified.

OBJECTIVE

To estimate the association of weight loss interventions with biomarkers of liver disease in NAFLD.

DATA SOURCES

MEDLINE, Embase, PsycINFO, CINAHL, Cochrane, and Web of Science databases along with 3 trial registries were searched from inception through January 2019.

STUDY SELECTION

Randomized clinical trials of people with NAFLD were included if they compared any intervention aiming to reduce weight (behavioral weight loss programs [BWLPs], pharmacotherapy, and surgical procedures) with no or lower-intensity weight loss intervention. The review followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers screened the studies, extracted the data, and assessed the risk of bias using the Cochrane tool. Pooled mean differences or odds ratios (ORs) were obtained from random-effects meta-analyses.

MAIN OUTCOMES AND MEASURES

Blood, radiologic, and histologic biomarkers of liver disease.

RESULTS

Twenty-two studies with 2588 participants (with a mean [SD] age of 45 [14] years and with approximately 66% male) were included. Fifteen studies tested BWLPs, 6 tested pharmacotherapy, and 1 tested a surgical procedure. The median (interquartile range) intervention duration was 6 (3-8) months. Compared with no or lower-intensity weight loss interventions, more-intensive weight loss interventions were statistically significantly associated with greater weight change (-3.61 kg; 95% CI, -5.11 to -2.12; I2 = 95%). Weight loss interventions were statistically significantly associated with improvements in biomarkers, including alanine aminotransferase (-9.81 U/L; 95% CI, -13.12 to -6.50; I2 = 97%), histologically or radiologically measured liver steatosis (standardized mean difference: -1.48; 95% CI, -2.27 to -0.70; I2 = 94%), histologic NAFLD activity score (-0.92; 95% CI, -1.75 to -0.09; I2 = 95%), and presence of nonalcoholic steatohepatitis (OR, 0.14; 95% CI, 0.04-0.49; I2 = 0%). No statistically significant change in histologic liver fibrosis was found (-0.13; 95% CI, -0.54 to 0.27; I2 = 68%). Twelve studies were at high risk of bias in at least 1 domain. In a sensitivity analysis of the 3 trials at low risk of bias, the estimates and precision of most outcomes did not materially change.

CONCLUSIONS AND RELEVANCE

The trials, despite some heterogeneity, consistently showed evidence of the association between weight loss interventions and improved biomarkers of liver disease in NAFLD in the short to medium term, although evidence on long-term health outcomes was limited. These findings appear to support the need to change the clinical guidelines and to recommend formal weight loss programs for people with NAFLD.

Nonalcoholic Fatty Liver Disease and Obesity Treatment

PURPOSE OF REVIEW

Nonalcoholic fatty liver disease (NAFLD), the most prevalent cause of chronic liver disease worldwide, is strongly associated with obesity and insulin resistance.

RECENT FINDINGS

Significant weight loss can improve NAFLD and nonalcoholic steatohepatitis (NASH). Diet and exercise that result in a sustained body weight reduction of 7-10% can improve liver fat content, NASH, and fibrosis. Vitamin E can be considered in patients with biopsy-proven NASH without diabetes, though caution must be used in those with prostate cancer. Pioglitazone improves liver histology, including fibrosis, and can be considered in patients with or without diabetes. Glucagon-like peptide-1 (GLP-1) antagonists may be beneficial in NASH, but more studies are needed before they can be recommended. Bariatric surgery, with resultant weight loss, can result in improvement in liver fat and inflammation. NAFLD treatment includes diet and exercise with a target 7-10% weight reduction. Treatment goals include improvements in liver fat content, liver inflammation, and fibrosis.

Effect of Lactobacillus paracasei N1115 and fructooligosaccharides in nonalcoholic fatty liver disease

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) is a growing health concern worldwide. Administration of probiotics and prebiotics has been proposed as a convenient and effective treatment. Our study aims to evaluate the therapeutic benefits of Lactobacillus paracasei N1115 (N1115) and fructooligosaccharides (FOS) by examining the histopathogenesis and underlying molecular events of NAFLD.

MATERIAL AND METHODS

An NAFLD mouse model was established by feeding C57BL/6 mice with a high-fat diet (HFD). N1115, FOS and synbiotics were administered for 16 weeks.

RESULTS

N1115, FOS and synbiotics alleviated HFD-induced hepatic steato-sis and release of tumor necrosis factor-α, and slowed the progression of cirrhosis. Compared to the HFD group, these dietary supplements reduced serum total triglyceride and cholesterol, and appeared to decrease the fasting blood glucose and insulin. Intraperitoneal glucose tolerance tests, homeostatic model assessment of insulin resistance and real-time PCR showed that the regimens could overcome insulin resistance. These findings were associated with the transcriptional repression of inflammatory factors such as lipopolysaccharides, Toll-like receptor 4 and nuclear factor-κB. Lastly, N1115, FOS, and synbiotics improved the intestinal barrier functions and histologic integrity. This was accompanied by the restoration of the p38 MAPK pathway and in-creased expression of the tight junction components occludin-1 and claudin-1.

CONCLUSIONS

N1115, FOS and synbiotics are effective in the prevention and treatment of NAFLD. Our data support the translation of these agents into clinical evaluation in human subjects with NAFLD and/or associated risk factors.

A structured literature review of interventions used in the management of nonalcoholic steatohepatitis (NASH)

Nonalcoholic steatohepatitis (NASH) is a chronic, progressive disease, that can advance to fibrosis, cirrhosis, and hepatocellular carcinoma. Despite being a leading cause of liver transplantation, there are no approved pharmacological treatments. Our aim was to identify literature on management options in NASH. Our structured review of interventions treating NASH patients from English language publications between 1 January 2007 and 25 September 2017 elicited 48 eligible references. Lifestyle management was identified as the mainstay of NASH therapy. Vitamin E and pioglitazone reported reductions in steatosis; however, although recommended for some, no therapies are indicated in NASH. Multiple investigational treatments reported efficacy in mild-to-moderate fibrosis in Phase II/III NASH trials. Lifestyle management, although the focus of clinical guidelines, is insufficient for patients progressing to advanced fibrosis. With no clear guidelines for patients requiring interventions beyond lifestyle modification, long-term outcomes data are needed, particularly in patients with moderate-to-severe fibrosis.

Pediatric NAFLD: an overview and recent developments in diagnostics and treatment

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in children and adults in industrialized countries. Besides liver-related morbidity, NAFLD is also associated with an increased risk of cardiovascular disease, type 2 diabetes and mortality at adult age. However, despite the high prevalence and serious complications, diagnosing and staging of disease remains complicated due to a lack of accurate screening tools and non-invasive methods to detect fibrosis. Areas covered: Recent insights in epidemiology, pathogenesis, diagnostic evaluation and treatment options in pediatric NAFLD are being reviewed, with a particular focus on new developments in diagnostic tools. Expert opinion: Due to their long life span, children with NAFLD are particularly at risk of complications in their lifetime. Therefore, an effective screening strategy for children to identify those with NAFLD at risk of complications is urgently needed. This is further underscored by new pharmacological therapies that are expected to become available in the next 5 years. Momentarily no accurate non-invasive method for diagnosing pediatric NAFLD is available. New promising biomarkers and imaging tools could hopefully provide better screening tools and could contribute to the development of a successful management plan to identify children with NAFLD.

Non-Alcoholic Fatty Liver Disease, an Overview

Nonalcoholic fatty liver disease (NAFLD) affects 25% of people worldwide. Patients with fatty liver disease are primarily asymptomatic. Currently, specialists are predicting that fatty liver related cirrhosis will the be leading reason for liver transplants in the next 10-20 years, displacing hepatitis C and alcohol related liver transplants. NAFLD exists on a spectrum of simple steatosis to steatosis with inflammation and different levels of fibrosis. It is currently estimated that 20% of simple steatosis patients will progress to nonalcoholic steatohepatitis (NASH). Patients with NASH are at risk for further progression to cirrhosis and hepatocellular carcinoma. There is no single factor that triggers progression from simple steatosis to NASH, however, we do know that NASH is more prevalent in patients with obesity, diabetes, and metabolic syndrome. NAFLD is thought to be the hepatic manifestation of metabolic syndrome, and is closely tied with hyperinsulinemia. Currently there are no approved FDA treatments for NAFLD. NAFLD is typically found incidentally on imaging such as abdominal ultrasound and CT. Elevations in alanine aminotransferase (ALT) may prompt the clinician to evaluate for NAFLD however ALT should not be used as a diagnostic tool. The gold standard for diagnosis of NAFLD and NASH is a liver biopsy. Only a liver biopsy can distinguish simple steatosis from NASH. In patients whom NAFLD is suspected, appropriate biochemical assessment and imaging should be evaluated. Also, the presence of fibrosis should be assessed. Weight loss and dietary modifications are currently the only recommendations provided to NAFLD patients. There is histological improvement seen in in patients whom lose 5-10% of their body weight. Certain dietary factors play a role in the development of NAFLD including excessive caloric intake and high fructose consumption. There are pharmacological treatments currently being studied as well as non-pharmacological agents. This overview focuses on evaluation, management and treatments in NAFLD.

Post hoc analyses of surrogate markers of non-alcoholic fatty liver disease (NAFLD) and liver fibrosis in patients with type 2 diabetes in a digitally supported continuous care intervention: an open-label, non-randomised controlled study

OBJECTIVE

One year of comprehensive continuous care intervention (CCI) through nutritional ketosis improves glycosylated haemoglobin(HbA1c), body weight and liver enzymes among patients with type 2 diabetes (T2D). Here, we report the effect of the CCI on surrogate scores of non-alcoholic fatty liver disease (NAFLD) and liver fibrosis.

METHODS

This was a non-randomised longitudinal study, including adults with T2D who were self-enrolled to the CCI (n=262) or to receive usual care (UC, n=87) during 1 year. An NAFLD liver fat score (N-LFS) >-0.640 defined the presence of fatty liver. An NAFLD fibrosis score (NFS) of >0.675 identified subjects with advanced fibrosis. Changes in N-LFS and NFS at 1 year were the main endpoints.

RESULTS

At baseline, NAFLD was present in 95% of patients in the CCI and 90% of patients in the UC. At 1 year, weight loss of ≥5% was achieved in 79% of patients in the CCI versus 19% of patients in UC (p<0.001). N-LFS mean score was reduced in the CCI group (-1.95±0.22, p<0.001), whereas it was not changed in the UC (0.47±0.41, p=0.26) (CCI vs UC, p<0.001). NFS was reduced in the CCI group (-0.65±0.06, p<0.001) compared with UC (0.26±0.11, p=0.02) (p<0.001 between two groups). In the CCI group, the percentage of individuals with a low probability of advanced fibrosis increased from 18% at baseline to 33% at 1 year (p<0.001).

CONCLUSIONS

One year of a digitally supported CCI significantly improved surrogates of NAFLD and advanced fibrosis in patients with T2D.

TRIAL REGISTRATION NUMBER

NCT02519309; Results.

Gegen Qinlian Decoction Attenuates High-Fat Diet-Induced Steatohepatitis in Rats via Gut Microbiota

Gut microbiota play an important role in modulating energy contribution, metabolism, and inflammation, and disruption of the microbiome population is closely associated with chronic metabolic diseases, such as nonalcoholic fatty liver disease (NAFLD). Gegen Qinlian decoction (GGQLD), a well-known traditional Chinese herbal medicine (CHM), was previously found to regulate lipid metabolism and attenuate inflammation during NAFLD pathogenesis. However, the underlying mechanism of this process, as well as how the gut microbiome is involved, remains largely unknown. In this study, we investigated the effect of varying doses of GGQLD on the total amount and distribution of gut bacteria in rats fed a high-fat diet (HFD) for 8 weeks. Our analysis indicates that Oscillibacter and Ruminococcaceae_g_unclassified are the dominant families in the HFD group. Further, HFD-dependent differences at the phylum, class, and genus levels appear to lead to dysbiosis, characterized by an increase in the Firmicutes/Bacteroidetes ratio and a dramatic increase in the Oscillibacter genus compared to the control group. Treatment with GGQLD, especially the GGQLL dose, improved these HFD-induced changes in intestinal flora, leading to increased levels of Firmicutes, Clostridia, Lactobacillus, bacilli, and Erysipelotrichales that were similar to the controls. Taken together, our data highlight the efficacy of GGQLD in treating NAFLD and support its clinical use as a treatment for NAFLD/NASH patients.

Exercising the hepatobiliary-gut axis. The impact of physical activity performance

BACKGROUND

Physical inactivity puts the populations at risk of several health problems, while regular physical activity brings beneficial effects on cardiovascular disease, mortality and other health outcomes, including obesity, glycaemic control and insulin resistance. The hepatobiliary tract is greatly involved in several metabolic aspects which include digestion and absorption of nutrients in concert with intestinal motility, bile acid secretion and flow across the enterohepatic circulation and intestinal microbiota. Several metabolic abnormalities, including nonalcoholic fatty liver as well as cholesterol cholelithiasis, represent two conditions explained by changes of the aforementioned pathways.

MATERIALS AND METHODS

This review defines different training modalities and discusses the effects of physical activity in two metabolic disorders, that is nonalcoholic fatty liver disease (NAFLD) and cholelithiasis. Emphasis is given to pathogenic mechanisms involving intestinal bile acids, microbiota and inflammatory status.

RESULTS

A full definition of physical activity includes the knowledge of aerobic and endurance exercise, metabolic equivalent tasks, duration, frequency and intensity, beneficial and harmful effects. Physical activity influences the hepatobiliary-gut axis at different levels and brings benefits to fat distribution, liver fat and gallbladder disease while interacting with bile acids as signalling molecules, intestinal microbiota and inflammatory changes in the body.

CONCLUSIONS

Several beneficial effects of physical activity are anticipated on metabolic disorders linking liver steatosis, gallstone disease, gut motility, enterohepatic circulation of signalling bile acids in relation to intestinal microbiota and inflammatory changes.

Lifestyle interventions for patients with nonalcoholic fatty liver disease: a network meta-analysis

Lifestyle interventions remain the first-line therapy for nonalcoholic fatty liver disease (NAFLD). This study aims to evaluate the individual impact of exercise and/or dietary interventions on the level of alanine aminotransferase (ALT), aspartate aminotransferase (AST), homeostasis model of assessment for insulin resistance index (HOMA-IR), and BMI. Randomized-controlled trials from patients diagnosed with NAFLD were included in the meta-analysis if they reported the associations between changes in ALT, AST, HOMA-IR, or BMI and types of lifestyle interventions. Nineteen eligible articles were included. Compared with observation, aerobic exercise training (AEx) plus diet [weighted mean difference (WMD)=-25.85; 95% confidence interval (CI): -43.90 to -7.80], AEx (WMD=-8.81; 95% CI: -20.22-2.60) and diet (WMD=-11.85; 95% CI: -47.65-24.95) showed significant efficacy in the improvement of ALT levels. Also AST, AEx plus diet showed a significant tendency to reduce AST levels. In addition, progressive resistance training (WMD=-1.70; 95% CI: -5.61-2.21) led to the most obvious reduction in HOMA-IR compared with observation, but appeared to show no significant effect in BMI (WMD=0.27; 95% CI: -0.48 to -0.07), whereas AEx plus diet (WMD=-0.96; 95% CI: -1.54 to -0.38 and WMD=-1.96; 95% CI: -2.79 to -1.12) showed great efficacy both in the improvement of HOMA-IR and BMI. AEx plus diet is the most effective intervention in the management of patients with NAFLD. Dietary intervention may be more effective in the improvements of aminotransferases, whereas exercise shows superiority in improving insulin sensitivity and reduction of BMI.

The Effects of Physical Exercise on Fatty Liver Disease

The increasing prevalence of obesity has made nonalcoholic fatty liver disease (NAFLD) the most common chronic liver disease. As a consequence, NAFLD and especially its inflammatory form nonalcoholic steatohepatitis (NASH) are the fastest increasing etiology of end-stage liver disease and hepatocellular carcinoma. Physical inactivity is related to the severity of fatty liver disease irrespective of body weight, supporting the hypothesis that increasing physical activity through exercise can improve fatty liver disease. This review summarizes the evidence for the effects of physical exercise on NAFLD and NASH. Several clinical trials have shown that both aerobic and resistance exercise reduce the hepatic fat content. From clinical and basic scientific studies, it is evident that exercise affects fatty liver disease through various pathways. Improved peripheral insulin resistance reduces the excess delivery of free fatty acids and glucose for free fatty acid synthesis to the liver. In the liver, exercise increases fatty acid oxidation, decreases fatty acid synthesis, and prevents mitochondrial and hepatocellular damage through a reduction of the release of damage-associated molecular patterns. In conclusion, physical exercise is a proven therapeutic strategy to improve fatty liver disease.

Plasticity of lifelong calorie-restricted C57BL/6J mice in adapting to a medium-fat diet intervention at old age

Calorie restriction (CR) is a dietary regimen that supports healthy aging. In this study, we investigated the systemic and liver‐specific responses caused by a diet switch to a medium‐fat (MF) diet in 24‐month‐old lifelong, CR‐exposed mice. This study aimed to increase the knowledge base on dietary alterations of gerontological relevance. Nine‐week‐old C57BL/6J mice were exposed either to a control, CR, or MF diet. At the age of 24 months, a subset of mice of the CR group was transferred to ad libitumMF feeding (CR‐MF). The mice were sacrificed at the age of 28 months, and then, biochemical and molecular analyses were performed. Our results showed that, despite the long‐term exposure to the CR regimen, mice in the CR‐MF group displayed hyperphagia, rapid weight gain, and hepatic steatosis. However, no hepatic fibrosis/injury or alteration in CR‐improved survival was observed in the diet switch group. The liver transcriptomic profile of CR‐MF mice largely shifted to a profile similar to the MF‐fed animals but leaving ~22% of the 1,578 differentially regulated genes between the CR and MF diet groups comparable with the expression of the lifelong CR group. Therefore, although the diet switch was performed at an old age, the CR‐MF‐exposed mice showed plasticity in coping with the challenge of a MF diet without developing severe liver pathologies.

The effect of low volume sprint interval training in patients with non-alcoholic fatty liver disease

OBJECTIVES

Exercise is an important part of disease management in patients with non-alcoholic fatty liver disease (NAFLD), but adherence to current exercise recommendations is poor. Novel low-volume sprint interval training (SIT) protocols with total training time commitments of ≤30 min per week have been shown to improve cardiometabolic risk and functional capacity in healthy sedentary participants, but the efficacy of such protocols in the management of NAFLD remains unknown. The aim of the present study was to examine whether a low-volume SIT protocol can be used to improve liver function, insulin resistance, body composition, physical fitness, cognitive function and general well-being in patients with NAFLD.

METHODS

In the present study, 7 men and 2 women with NAFLD (age: 45 ± 8 y, BMI: 28.7 ± 4.1 kg·m^-2) completed a 6-week control period followed by 6 weeks of twice-weekly SIT sessions (5-10 × 6-s 'all-out' cycle sprints). Body composition, blood pressure, liver function, metabolic function, functional capacity, cognitive function and quality of life were assessed at baseline, following the control period, and following the SIT intervention.

RESULTS

Walking speed during the walk test (+12%), estimated V̇O₂max (+8%), verbal fluency (+44%), and blood platelet count (+12%; all p < 0.05) significantly increased during the control period. These measures remained significantly raised compared to baseline following the SIT intervention, but did not significantly change any further compared to the post-control time-point. Diastolic blood pressure decreased from 87 ± 10 to 77 ± 8 mm Hg from the end of the control period to the end of the SIT intervention (p < 0.05).

CONCLUSION

This study does not support the use of 6 weeks of a low volume SIT protocol involving twice-weekly sessions with 5-10 × 6-s 'all-out' cycle sprints as an intervention for NAFLD disease management.

Treatment of NAFLD with diet, physical activity and exercise

Lifestyle intervention can be effective when treating non-alcoholic fatty liver diseases (NAFLD) patients. Weight loss decreases cardiovascular and diabetes risk and can also regress liver disease. Weight reductions of ⩾10% can induce a near universal non-alcoholic steatohepatitis resolution and fibrosis improvement by at least one stage. However, modest weight loss (>5%) can also produce important benefits on the components of the NAFLD activity score (NAS). Additionally, we need to explore the role of total calories and type of weight loss diet, micro- and macronutrients, evidence-based benefits of physical activity and exercise and finally support these modifications through established behavioural change models and techniques for long-term maintenance of lifestyle modifications. Following a Mediterranean diet can reduce liver fat even without weight loss and is the most recommended dietary pattern for NAFLD. The Mediterranean diet is characterised by reduced carbohydrate intake, especially sugars and refined carbohydrates (40% of the calories vs. 50-60% in a typical low fat diet), and increased monounsaturated and omega-3 fatty acid intake (40% of the calories as fat vs. up-to 30% in a typical low fat diet). Both TV sitting (a reliable marker of overall sedentary behaviour) and physical activity are associated with cardio-metabolic health, NAFLD and overall mortality. A 'triple hit behavioural phenotype' of: i) sedentary behaviour, ii) low physical activity, and iii) poor diet have been defined. Clinical evidence strongly supports the role of lifestyle modification as a primary therapy for the management of NAFLD and NASH. This should be accompanied by the implementation of strategies to avoid relapse and weight regain.

Yinchen Linggui Zhugan Decoction Ameliorates Nonalcoholic Fatty Liver Disease in Rats by Regulating the Nrf2/ARE Signaling Pathway

Yinchen Linggui Zhugan Decoction (YCLGZGD) is the combination of Linggui Zhugan (LGZGD) and Yinchenhao (YCHD) decoctions, two famous traditional Chinese medicine prescriptions. In previous studies, we found that Yinchen Linggui Zhugan Decoction (YCLGZGD) could regulate lipid metabolism disorder and attenuate inflammation in pathological process of nonalcoholic fatty liver disease (NAFLD). However, the exact underlying mechanism remains unknown. The aim of this study was to explore the effect of Yinchen Linggui Zhugan Decoction on experimental NAFLD and its mechanism in rats with high-fat diet (HFD) which was established by 8-week administration of HFD. YCLGZGD, LGZGD, and YCHD were administered daily for 4 weeks, after which the rats were euthanized. The level of blood lipid, liver enzymes, H&E, and Oil Red O staining were determined to evaluate NAFLD severity. Western blotting and real-time polymerase chain reaction were, respectively, used to determine hepatic protein and gene expression of Keap1, Nrf2, NQO1, and HO-1. Oral YCLGZGD ameliorated HFD-induced NAFLD. Furthermore, YCLGZGD increased the protein and gene expression of Nrf2, NQO1, and HO-1 without changing Keap1. Overall, these results suggest that YCLGZGD ameliorates HFD-induced NAFLD in rats by upregulating the Nrf2/ARE signaling pathway.

Efficacy of dietary and physical activity intervention in non-alcoholic fatty liver disease: a systematic review

Background

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide, with prevalence above 30% in many adult populations. Strongly associated with obesity, weight loss through diet and physical activity is the mainstay of its management. Weight loss can be difficult to achieve and maintain however, and uncertainty exists as to which lifestyle changes are most effective.

Objective

The aim of this work was to systematically evaluate randomised controlled trials assessing diet, exercise or combination interventions aimed at reducing steatosis or markers of NAFLD activity.

Design

Medline, Scopus and Cochrane databases were searched from 1 January 1980 through to 31 July 2016, for intervention trials assessing the effects of diet, weight loss, exercise or any combination thereof, on NAFLD disease markers in human adults. Risk of publication bias and study quality was assessed using the American Dietetic Association Quality Criteria Checklist.

Results

From a total of 1710 identified records, 24 articles met the inclusion and exclusion criteria; 6 assessed weight loss using dietary restriction, 10 assessed exercise and 8 were combination interventions. While all of the trials demonstrated significant reduction in steatosis and/or markers of NAFLD activity, combination interventions appear to be the most effective at improving NAFLD. Results suggest that 5–10% weight loss using a modestly hypocaloric diet of 500 kcal less per day than calculated energy requirement, in combination with 30–60 min exercise on 3–5 days per week should be recommended.

Conclusions

We conclude this amount of weight loss is achievable in the trial setting but is challenging in the clinical environment. High-intensity, multidisciplinary intervention in specialist clinics is likely to be required in order to manage NAFLD by lifestyle modification alone. This systematic review protocol was registered prospectively at PROSPERO as CRD42016032764.

Effects of lifestyle modification on liver enzyme and Fibroscan in Indian patients with non-alcoholic fatty liver disease

Background and aims

Non-alcoholic fatty liver disease (NAFLD) is remarkably increasing in developing countries like India, in parallel with the increasing incidence of obesity. Lifestyle modification is a recommended treatment for NAFLD. In most of the previous studies, improvement after lifestyle modification was assessed by liver fibrosis through liver biopsy, but we cannot do a serial liver biopsy in every NAFLD patient. Liver fibrosis can also be assessed by fibroscan non-invasively in NAFLD. This study was designed to evaluate the effect of lifestyle modification on liver enzymes and Fibroscan values in a population with NAFLD.

Methods

Initially, 50 NAFLD patients were included in this prospective follow-up study; however, after 6 months of lifestyle modification, only 39 participants were studied. During both the first and second consultations, Fibroscan was carried out. All participants underwent a careful interview, anthropometry measurements and radiological and biochemical tests during every consultation.

Results

After 6 months of lifestyle modification, Fibroscan values improved significantly (8.31 ± 0.11kPa vs 7.87 ± 0.12kPa, p=0.009). Alanine aminotransferase (ALT) values also showed improvement during the second consultation (97.25 ± 2.62 U/L vs 66.69 ± 3.95 U/L, p <0.001).

Conclusion

Measured by Fibroscan and liver enzymes, it has been found that lifestyle modification is an effective therapy to downgrade hepatic injury in NAFLD patients. Serial Fibroscan can be used to assess the treatment response in NAFLD patients due to its non-invasive nature.

Effects of lifestyle interventions on clinical characteristics of patients with non-alcoholic fatty liver disease: A meta-analysis

BACKGROUND/OBJECTIVES

Although lifestyle modifications remain the cornerstone therapy for non-alcoholic fatty liver disease (NAFLD), the optimal lifestyle intervention is still controversial. The aim of this meta-analysis was to evaluate the effect of exercise and/or dietary interventions, type or intensity of exercise and type of diet, on liver function outcomes (liver enzymes, intrahepatic fat and liver histology), as well as on anthropometric and glucose metabolism parameters in NAFLD patients.

SUBJECTS/METHODS

Literature search was performed in Scopus and US National Library of Medicine databases to identify all randomized controlled clinical trials (RCTs) in adult patients with NAFLD, diagnosed through imaging techniques or liver biopsy, published in English between January 2005 and August 2016. Studies' quality was evaluated using the Cochrane Risk of Bias Tool. Heterogeneity was tested using the Cochran's Q test and measured inconsistency by I². Effect size was calculated as the standardized mean difference (SMD). The meta-analysis was performed in accordance with PRISMA guidelines.

RESULTS

Twenty RCTs with 1073 NAFLD patients were included. Compared to standard care, exercise improved serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) (all P<0.05). Ιntrahepatic fat also improved, irrespectively of weight change (SMD=-0.98, 95% CI: -1.30 to -0.66). Regarding the type of exercise, aerobic compared to resistance exercise did not yield any superior improvements on liver parameters, whereas moderate-to-high volume moderate-intensity continuous training was more beneficial compared to continuous low-to-moderate-volume moderate-intensity training or high intensity interval training. Interventions combining exercise and diet showed decreases in ALT (P<0.01) and improvement in NAFLD activity score (SMD=-0.61, 95% CI: -1.09 to -0.13). Moderate-carbohydrate diets yielded similar changes in liver enzymes compared to low/moderate-fat diets.

CONCLUSIONS

Exercise alone or combined with dietary intervention improves serum levels of liver enzymes and liver fat or histology. Exercise exerts beneficial effects on intrahepatic triglycerides even in the absence of weight loss.

Effectiveness of Omega-3 Polyunsaturated Fatty Acids in Non-Alcoholic Fatty Liver Disease: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a clinical syndrome with the main characteristic of diffuse liver cells with fatty changes. The clinical evolution of NAFLD includes simple non-alcoholic fatty liver, non-alcoholic steatohepatitis (NASH), liver fibrosis and cirrhosis, and even hepatocellular carcinoma.

METHODS AND FINDINGS

We conducted this review to identify the effectiveness of omega-3 polyunsaturated fatty acids (ω-3 PUFA) in NAFLD. We searched PubMed, Cochrane Library and Embase. All randomized controlled trials (RCTs) of ω-3 PUFA treatment for NAFLD were considered. Two reviewers assessed the quality of each study and collected data independently. Disagreements were resolved by discussion among the reviewers and any of the other authors of the paper. We performed a meta-analysis and reported summary estimates of outcomes as inverse variance (IV), fixed or random, with 95% confidence intervals (CIs). We included seven RCTs involving 442 patients (227 for the experimental group and 215 for the control group). All the patients were divided into two groups: one treated with ω-3 PUFA and the other was the control group (generally placebo). The demographics of the ω-3 PUFA and control groups were comparable. Beneficial changes in alanine aminotransferase (ALT) (IV 95% CI: -7.61 [-12.83 to -2.39], p = 0.004), total cholesterol (TC) (IV 95% CI: -13.41 [-21.44 to -5.38], p = 0.001), triglyceride (TG) (IV 95% CI: -43.96 [-51.21 to -36.71], p<0.00001) and high-density lipoprotein cholesterol (HDL-C) (IV 95% CI: 6.97 [2.05 to 11.90], p = 0.006) favored ω-3 PUFA treatment. Omega-3 PUFA tended towards a beneficial effect on aspartate aminotransferase (AST) (IV 95% CI: -6.89 [-17.71 to 3.92], p = 0.21), γ-glutamyl transferase (GGT) (IV 95% CI: -8.28 [-18.38 to 1.83], p = 0.11) and low-density lipoprotein cholesterol (LDL-C) (IV 95% CI: -7.13 [-14.26 to 0.0], p = 0.05).

CONCLUSIONS

Supplementation with ω-3 PUFA is a practical and effective treatment for NAFLD to decrease ALT, TC and increase HDL-C, especially to decrease TG. Omega-3 PUFA also has a tendency toward a beneficial effect on AST, GGT and LDL-C. More high-quality, large RCTs are needed to validate our findings.

Exercise-based Interventions for Nonalcoholic Fatty Liver Disease: A Meta-analysis and Meta-regression

BACKGROUND & AIMS

The burden of nonalcoholic fatty liver disease (NAFLD) is increasing worldwide. We performed a meta-analysis to determine the effectiveness of exercise-based lifestyle interventions on liver-specific end points in populations with NAFLD and underlying metabolic disorders such as obesity, type 2 diabetes, or metabolic syndrome.

METHODS

We searched PubMed-MEDLINE, Embase, and the Cochrane Central register through October 21, 2015 for randomized trials of exercise-based lifestyle interventions on end points such as intrahepatic lipid content and blood levels of alanine and aspartate aminotransferases. Effect sizes are reported as standardized mean difference and weighted mean difference values. To investigate heterogeneity, we performed sensitivity and meta-regression analyses. Results were reported according to the PRISMA statement.

RESULTS

We analyzed data from 28 trials. Physical activity, independently from diet change, was associated with a significant reduction in intrahepatic lipid content (standardized mean difference, -0.69; 95% confidence interval [CI], -0.90 to -0.48) and with reductions in alanine aminotransferase (weighted mean difference, -3.30 IU/L; 95% CI, 5.57 to -1.04) and aspartate aminotransferase (weighted mean difference, -4.85 IU/L; 95% CI, -8.68 to -1.02). By meta-regression, we found individuals with increasing body mass index to be increasingly more likely to benefit from the intervention (beta coefficient = -0.10; P = .037). We recorded no effect modification by variables related to the intensity of the intervention.

CONCLUSIONS

In a meta-analysis of randomized trials, we found strong evidence that physical activity reduces intrahepatic lipid content and markers of hepatocellular injury in patients with NAFLD. This effect correlated with baseline body mass index.

Non-alcoholic fatty liver disease in 2016

INTRODUCTION

Non-alcoholic fatty liver disease is the commonest cause of liver disease worldwide, and is rapidly becoming the leading indication for liver transplantation.

SOURCES OF DATA

Original articles, reviews and meta-analyses, guidelines.

AREAS OF AGREEMENT

NAFLD strongly correlates with obesity and insulin resistance; currently, the best management strategy is weight loss and treatment of the metabolic syndrome.

AREAS OF CONTROVERSY

Recent data suggest that the presence of fibrosis and not non-alcoholic steatohepatitis (NASH) is the predictor of clinical outcome.

GROWING POINTS

Many phase 2 and 3 trials are underway. Drugs hoped to be effective are obeticholic acid, elafibranor, glucagon-like peptide-1 analogues and CCR2/5 inhibitors.

AREAS TIMELY FOR DEVELOPING RESEARCH

Improved understanding of the pathophysiology of NAFLD should help us identify which patients progress to significant liver disease and to develop therapies to target this population.

Effectiveness of exercise in hepatic fat mobilization in non-alcoholic fatty liver disease: Systematic review

AIM: To investigate the efficacy of exercise interventions on hepatic fat mobilization in non-alcoholic fatty liver disease (NAFLD) patients.

METHODS: Ovid-Medline, PubMed, EMBASE and Cochrane database were searched for randomized trials and prospective cohort studies in adults aged ≥ 18 which investigated the effects of at least 8 wk of exercise only or combination with diet on NAFLD from 2010 to 2016. The search terms used to identify articles, in which exercise was clearly described by type, duration, intensity and frequency were: “NASH”, “NAFLD”, “non-alcoholic steatohepatitis”, “non-alcoholic fatty liver disease”, “fat”, “steatosis”, “diet”, “exercise”, “MR spectroscopy” and “liver biopsy”. NAFLD diagnosis, as well as the outcome measures, was confirmed by either hydrogen-magnetic resonance spectroscopy (H-MRS) or biopsy. Trials that included dietary interventions along with exercise were accepted if they met all criteria.

RESULTS: Eight studies met selection criteria (6 with exercise only, 2 with diet and exercise with a total of 433 adult participants). Training interventions ranged between 8 and 48 wk in duration with a prescribed exercise frequency of 3 to 7 d per week, at intensities between 45% and 75% of VO₂ peak. The most commonly used imaging modality was H-MRS and one study utilized biopsy. The effect of intervention on fat mobilization was 30.2% in the exercise only group and 49.8% in diet and exercise group. There was no difference between aerobic and resistance exercise intervention, although only one study compared the two interventions. The beneficial effects of exercise on intrahepatic triglyceride (IHTG) were seen even in the absence of significant weight loss. Although combining an exercise program with dietary interventions augmented the reduction in IHTG, as well as improved measures of glucose control and/or insulin sensitivity, exercise only significantly decreased hepatic lipid contents.

CONCLUSION: Prescribed exercise in subjects with NAFLD reduces IHTG independent of dietary intervention. Diet and exercise was more effective than exercise alone in reducing IHTG.

Development and validation of a noninvasive prediction model for nonalcoholic steatohepatitis resolution after lifestyle intervention

Liver biopsy is the gold standard method to assess nonalcoholic steatohepatitis (NASH) resolution after therapeutic interventions. We developed and validated a simple and noninvasive scoring system to predict NASH resolution without fibrosis worsening after 1 year of lifestyle intervention. This was a prospective cohort study conducted in 261 patients with histologically proven NASH who were treated with lifestyle changes for 52 weeks and underwent a second liver biopsy to confirm NASH resolution. We divided the data into development (140 subjects) and validation (121 individuals) sets. NASH resolution occurred in 28% (derivation group) and 27% (validation group). At the multivariable analysis, weight loss (odds ratio [OR] = 2.75, 95% confidence interval [CI] 1.65-4.58; P < 0.01), type 2 diabetes (OR = 0.04, 95% CI 0.005-0.49; P = 0.01), normal levels of alanine aminotransferase at the end of intervention (OR = 9.84, 95% CI 2.21-44.1; P < 0.01), age (OR = 0.89, 95% CI 0.83-0.97; P = 0.01), and a nonalcoholic fatty liver activity score ≥5 (OR = 0.08, 95% CI 0.01-0.43; P < 0.01) were independent predictors of NASH resolution. The area under the receiver operating characteristic curve of the selected model was 0.956 and 0.945 in the derivation and validation cohorts, respectively. Using a score threshold of ≤46.15, negative predictive values were 92% in the derivation and validation groups, respectively. By applying a cutoff ≥69.72, positive predictive values were 92% and 89% in the derivation and validation groups, respectively. Using both cutoffs, a liver biopsy would have been avoided in 229 (88%) of 261 patients, with a correct prediction in 209 (91%)

CONCLUSIONS

A noninvasive prediction model including weight loss, type 2 diabetes, alanine aminotransferase normalization, age, and a nonalcoholic fatty liver activity score ≥5 may be useful to identify NASH resolution in patients under lifestyle intervention. (Hepatology 2016;63:1875-1887).

Diet, weight loss, and liver health in nonalcoholic fatty liver disease: Pathophysiology, evidence, and practice

Fatty liver accumulation results from an imbalance between lipid deposition and removal, driven by the hepatic synthesis of triglycerides and de novo lipogenesis. The habitual diet plays a relevant role in the pathogenesis of nonalcoholic fatty liver disease (NAFLD), and both risky (e.g., fructose) and protective foods (Mediterranean diet) have been described, but the contribution of excess calories remains pivotal. Accordingly, weight loss is the most effective way to promote liver fat removal. Several controlled studies have confirmed that an intense approach to lifestyle changes, carried on along the lines of cognitive-behavior treatment, is able to attain the desired 7%-10% weight loss, associated with reduced liver fat, nonalcoholic steatohepatitis (NASH) remission, and also reduction of fibrosis. Even larger effects are reported after bariatric surgery-induced weight loss in NAFLD, where 80% of subjects achieve NASH resolution at 1-year follow-up. These results provide solid data to evaluate the safety and effectiveness of the pharmacological treatment of NASH. The battle against metabolic diseases, largely fueled by increased liver fat, needs a comprehensive approach to be successful in an obesiogenic environment. In this review, we will discuss the role of hepatic lipid metabolism, genetic background, diet, and physical activity on fatty liver. They are the basis for a lifestyle approach to NAFLD treatment. (Hepatology 2016;63:2032-2043).

Lifestyle and Dietary Interventions in the Management of Nonalcoholic Fatty Liver Disease

NAFLD is the leading cause of chronic liver disease in the Western world with an estimated prevalence of 20-30 %. Lifestyle interventions targeted at weight loss through dietary interventions and exercise are the most effective treatment, but only a minority of patients are able to achieve and sustain the necessary intervention targets. Weight loss of 3-5 % has been associated with a reduction of hepatic steatosis while weight loss of ≥5-7 % has correlated with resolution of NASH in some studies. Greater reductions in weight loss (≥10 %) may improve hepatic fibrosis. In the absence of weight loss, no specific diet has demonstrated superiority. Physical activity can improve hepatic steatosis and metabolic indices even without weight loss. Diet coupled with exercise can produce significant weight loss and may improve histologic components of the NAFLD activity score. While formal guidelines for diet and exercise in NAFLD are lacking, adherence to diet and exercise recommendations similar to those from the American Diabetes Association for diabetic care seems reasonable. Dietary supplementation with vitamin E in non-diabetics with biopsy-proven NASH has been shown to improve NAFLD activity score. The role for other macronutrients, micronutrients, antioxidants, and probiotics in the treatment of NAFLD remains limited.

Effect of Weight Loss, Diet, Exercise, and Bariatric Surgery on Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome. NAFLD is the most common liver disease in developed countries. Weight reduction of 3% to 5% is associated with improved steatosis; reductions of 5% to 7% are necessary for decreased inflammation; with 7% to 10%, individuals may experience NAFLD/NASH remission and regression of fibrosis. No specific dietary intervention has proven beneficial beyond calorie restriction. Physical activity without weight loss seems to decrease hepatic steatosis. Bariatric surgery is associated with decreased cardiovascular risk and improved overall mortality in addition to reduction in hepatic steatosis, inflammation, and fibrosis.

The Metabolic Syndrome and Its Influence on Nonalcoholic Steatohepatitis

Nonalcoholic steatohepatitis (NASH) and the metabolic syndrome (MetS) are highly prevalent in the Western population. Their pathogenesis is closely linked to insulin resistance, which serves as a therapeutic target for the management of these conditions. This review article reviews the research supporting the influence of MetS on NASH and includes studies supporting their similar epidemiology, pathogenesis, and treatment.

A Comprehensive Updated Review of Pharmaceutical and Nonpharmaceutical Treatment for NAFLD

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in the western world with prevalence of 20–33%. NAFLD comprises a pathological spectrum. Nonalcoholic fatty liver (NAFL) is at one end and consists of simple hepatic steatosis. On the contrary, nonalcoholic steatohepatitis (NASH) consists of steatosis, inflammation, and ballooning degeneration and can progress to cirrhosis. Despite the rising incidence, definitive treatment for NAFLD, specifically NASH, has not yet been established. Lifestyle modification with dietary changes combined with regular aerobic exercise, along with multidisciplinary approach including cognitive behavior therapy, has been shown to be an effective therapeutic option, even without a significant weight loss. Pioglitazone and vitamin E have shown to be most effective in NASH patients. Surgery and weight loss medication are effective means of weight loss but can potentially worsen NASH related fibrosis. Other agents such as n-3 polyunsaturated fatty acids, probiotics, and pentoxifylline along with herbal agent such as milk thistle as well as daily intake of coffee have shown potential benefits, but further well organized studies are definitely warranted. This review focuses on the available evidence on pharmaceutical and nonpharmaceutical therapy in the treatment and the prevention of NAFLD, primarily NASH.

Co-Administration of Cholesterol-Lowering Probiotics and Anthraquinone from Cassia obtusifolia L. Ameliorate Non-Alcoholic Fatty Liver

Non-alcoholic fatty liver disease (NAFLD) has become a common liver disease in recent decades. No effective treatment is currently available. Probiotics and natural functional food may be promising therapeutic approaches to this disease. The present study aims to investigate the efficiency of the anthraquinone from Cassia obtusifolia L. (AC) together with cholesterol-lowering probiotics (P) to improve high-fat diet (HFD)-induced NAFLD in rat models and elucidate the underlying mechanism. Cholesterol-lowering probiotics were screened out by MRS-cholesterol broth with ammonium ferric sulfate method. Male Sprague-Dawley rats were fed with HFD and subsequently administered with AC and/or P. Lipid metabolism parameters and fat synthesis related genes in rat liver, as well as the diversity of gut microbiota were evaluated. The results demonstrated that, compared with the NAFLD rat, the serum lipid levels of treated rats were reduced effectively. Besides, cholesterol 7α-hydroxylase (CYP7A1), low density lipoprotein receptor (LDL-R) and farnesoid X receptor (FXR) were up-regulated while the expression of 3-hydroxy-3-methyl glutaryl coenzyme A reductase (HMGCR) was reduced. The expression of peroxisome proliferator activated receptor (PPAR)-α protein was significantly increased while the expression of PPAR-γ and sterol regulatory element binding protein-1c (SREBP-1c) was down-regulated. In addition, compared with HFD group, in AC, P and AC+P group, the expression of intestinal tight-junction protein occludin and zonula occluden-1 (ZO-1) were up-regulated. Furthermore, altered gut microbiota diversity after the treatment of probiotics and AC were analysed. The combination of cholesterol-lowering probiotics and AC possesses a therapeutic effect on NAFLD in rats by up-regulating CYP7A1, LDL-R, FXR mRNA and PPAR-α protein produced in the process of fat metabolism while down-regulating the expression of HMGCR, PPAR-γ and SREBP-1c, and through normalizing the intestinal dysbiosis and improving the intestinal mucosal barrier function.

Intensive lifestyle treatment for non-alcoholic fatty liver disease in children with severe obesity: inpatient versus ambulatory treatment

BACKGROUND/AIMS

Lifestyle intervention is the only established therapy for non-alcoholic fatty liver disease (NAFLD). The optimal treatment schedule and predictors of response of this treatment have not been established in children. We aimed to evaluate the 2-year efficacy of an inpatient versus ambulatory intensive lifestyle intervention for treating NAFLD in children with severe obesity.

METHODS

A cohort study of 51 severely obese non-diabetic children (mean age 14.7 (±2.4) years; BMI-z-score 3.5 (±0.5)) with liver steatosis were non-randomly allocated to inpatient treatment (2 or 6 months), ambulatory treatment or usual care. Proton Magnetic Resonance Spectroscopy determined liver steatosis and serum alanine aminotransferase (ALT) at 6 months were the primary outcome measures. Baseline variables were evaluated as predictors of treatment response.

RESULTS

Liver steatosis had disappeared in 43, 29 and 22% and serum ALT normalized in 41, 33 and 6% at the end of 6 months in the inpatient, ambulatory or usual care treatment groups, respectively. Only the proportions of ALT normalization in inpatient and ambulatory treatment compared with usual care were significantly higher. Treatment effects of inpatient and ambulatory treatment were sustained at 1.5 years follow-up. No baseline characteristic, including PNPLA3 polymorphism or leptin, was consistently predictive for treatment response.

CONCLUSIONS

A 6-month intensive inpatient and ambulatory lifestyle treatment in children with severe obesity reverses NAFLD in a minority of patients. This study suggests that inpatient compared with ambulatory intensive treatment does not importantly increase treatment success. Further efforts to optimize and individualize lifestyle interventions and additional treatments options are needed particular for children with severe obesity resistant to conventional lifestyle interventions.

Physical activity as a treatment of non-alcoholic fatty liver disease: A systematic review

AIM

To review the effectiveness of exercise as a therapy for nonalcoholic fatty liver disease (NAFLD) and potential benefits in treating insulin resistance and atherosclerosis.

METHODS

Medline (EBSCOhost) and PubMed were searched for English-language randomized controlled trials and prospective cohort studies in human adults aged ≥ 18 which investigated the various effects of exercise alone, a combination of exercise and diet, or exercise and diet coupled with behavioral modification on NAFLD from 2010 to Feburary 2015.

RESULTS

Eighteen of 2298 available studies were chosen for critical review, which included 6925 patients. Nine (50%) studies were randomized controlled trials. Five (27.8%) studies utilized biopsy to examine the effects of physical activity on hepatic histology. The most commonly employed imaging modality to determine change in hepatic steatosis was hydrogen-magnetic resonance spectroscopy. Only two studies examined the effects of low impact physical activity for patients with significant mobility limitations and one compared the efficacy of aerobic and resistance exercise. No studies examined the exact duration of exercise required for hepatic and metabolic improvement in NAFLD.

CONCLUSION

While exercise improved hepatic steatosis and underlying metabolic abnormalities in NAFLD, more studies are needed to define the most beneficial form and duration of exercise treatment.

Effects of total fat intake on body weight

BACKGROUND

In order to prevent overweight and obesity in the general population we need to understand the relationship between the proportion of energy from fat and resulting weight and body fatness in the general population.

OBJECTIVES

To assess the effects of proportion of energy intake from fat on measures of weight and body fatness (including obesity, waist circumference and body mass index) in people not aiming to lose weight, using all appropriate randomised controlled trials (RCTs) and cohort studies in adults, children and young people

SEARCH METHODS

We searched CENTRAL to March 2014 and MEDLINE, EMBASE and CINAHL to November 2014. We did not limit the search by language. We also checked the references of relevant reviews.

SELECTION CRITERIA

Trials fulfilled the following criteria: 1) randomised intervention trial, 2) included children (aged ≥ 24 months), young people or adults, 3) randomised to a lower fat versus usual or moderate fat diet, without the intention to reduce weight in any participants, 4) not multifactorial and 5) assessed a measure of weight or body fatness after at least six months. We also included cohort studies in children, young people and adults that assessed the proportion of energy from fat at baseline and assessed the relationship with body weight or fatness after at least one year. We duplicated inclusion decisions and resolved disagreement by discussion or referral to a third party.

DATA COLLECTION AND ANALYSIS

We extracted data on the population, intervention, control and outcome measures in duplicate. We extracted measures of weight and body fatness independently in duplicate at all available time points. We performed random-effects meta-analyses, meta-regression, subgrouping, sensitivity and funnel plot analyses.

MAIN RESULTS

We included 32 RCTs (approximately 54,000 participants) and 30 sets of analyses of 25 cohorts. There is consistent evidence from RCTs in adults of a small weight-reducing effect of eating a smaller proportion of energy from fat; this was seen in almost all included studies and was highly resistant to sensitivity analyses. The effect of eating less fat (compared with usual diet) is a mean weight reduction of 1.5 kg (95% confidence interval (CI) -2.0 to -1.1 kg), but greater weight loss results from greater fat reductions. The size of the effect on weight does not alter over time and is mirrored by reductions in body mass index (BMI) (-0.5 kg/m(2), 95% CI -0.7 to -0.3) and waist circumference (-0.3 cm, 95% CI -0.6 to -0.02). Included cohort studies in children and adults most often do not suggest any relationship between total fat intake and later measures of weight, body fatness or change in body fatness. However, there was a suggestion that lower fat intake was associated with smaller increases in weight in middle-aged but not elderly adults, and in change in BMI in the highest validity child cohort.

AUTHORS' CONCLUSIONS

Trials where participants were randomised to a lower fat intake versus usual or moderate fat intake, but with no intention to reduce weight, showed a consistent, stable but small effect of low fat intake on body fatness: slightly lower weight, BMI and waist circumference compared with controls. Greater fat reduction and lower baseline fat intake were both associated with greater reductions in weight. This effect of reducing total fat was not consistently reflected in cohort studies assessing the relationship between total fat intake and later measures of body fatness or change in body fatness in studies of children, young people or adults.

Weight Loss Through Lifestyle Modification Significantly Reduces Features of Nonalcoholic Steatohepatitis

BACKGROUND & AIMS

It is not clear how weight loss affects histologic features of liver in patients with nonalcoholic steatohepatitis (NASH). We examined the association between the magnitude of weight loss through lifestyle modifications and changes in histologic features of NASH.

METHODS

We conducted a prospective study of 293 patients with histologically proven NASH who were encouraged to adopt recommended lifestyle changes to reduce their weight over 52 weeks, from June 2009 through May 2013, at a tertiary medical center in Havana, Cuba. Liver biopsies were collected when the study began and at week 52 of the diet and were analyzed histologically.

RESULTS

Paired liver biopsies were available from 261 patients. Among 293 patients who underwent lifestyle changes for 52 weeks, 72 (25%) achieved resolution of steatohepatitis, 138 (47%) had reductions in nonalcoholic fatty liver disease activity score (NAS), and 56 (19%) had regression of fibrosis. At week fifty-two, 88 subjects (30%) had lost ≥5% of their weight. Degree of weight loss was independently associated with improvements in all NASH-related histologic parameters (odds ratios = 1.1-2.0; P < .01). A higher proportion of subjects with ≥5% weight loss had NASH resolution (51 of 88 [58%]) and a 2-point reduction in NAS (72 of 88 [82%]) than subjects who lost <5% of their weight (P < .001). All patients who lost ≥10% of their weight had reductions NAS, 90% had resolution of NASH, and 45% had regression of fibrosis. All patients who lost 7%-10% of their weight and had few risk factors also had reduced NAS. In patients with baseline characteristics that included female sex, body mass index ≥35, fasting glucose >5.5 mmol/L, and many ballooned cells, NAS scores decreased significantly with weight reductions ≥10%.

CONCLUSIONS

A greater extent of weight loss, induced by lifestyle changes, is associated with the level of improvement in histologic features of NASH. The highest rates of NAS reduction, NASH resolution, and fibrosis regression occurred in patients with weight losses ≥10%.

Treatment of nonalcoholic steatohepatitis in adults: present and future

Nonalcoholic steatohepatitis has become one of the most common liver-related health problems. This condition has been linked to an unhealthy diet and weight gain, but it can also be observed in nonobese people. The standard of care is represented by the lifestyle intervention. However, because this approach has several limitations, such as a lack of compliance, the use of many drugs has been proposed. The first-line pharmacological choices are vitamin E and pioglitazone, both showing a positive effect on transaminases, fat accumulation, and inflammation. Nevertheless, vitamin E has no proven effect on fibrosis and on long-term morbidity and mortality and pioglitazone has a negative impact on weight. Other drugs have been studied such as metformin, ursodeoxycholic acid, statins, pentoxiphylline, and orlistat with only partially positive results. Among the emerging treatments, telmisartan is particularly interesting as it seems to have an impact on insulin resistance, liver steatosis, inflammation, and fibrosis. However, the pathogenesis of steatohepatitis is highly complex and is determined by different parallel hits; indeed, the association of different drugs that act on various levels has been suggested. In conclusion, lifestyle intervention should be optimised and the associations of different drugs should be tested in large studies with long-term outcomes.

Dietary blueberry and bifidobacteria attenuate nonalcoholic fatty liver disease in rats by affecting SIRT1-mediated signaling pathway

NAFLD model rats were established and divided into NAFLD model (MG group), SIRT1 RNAi (SI group), blueberry juice (BJ group), blueberry juice + bifidobacteria (BJB group), blueberry juice + SIRT1 RNAi (BJSI group), and blueberry juice + bifidobacteria + SIRT1 RNAi groups (BJBSI group). A group with normal rats was a control group (CG). BJB group ameliorated NAFLD, which was better than BJ group (P < 0.05). The lipid accumulation was lower in CG, BJ, and BJB groups than that in MG, SI, BJSI, and BJBSI groups (P < 0.05). The levels of SIRT1 and PPAR-α were higher in CG, BJ, and BJB groups than those in MG, SI, BJSI, and BJBSI groups (P < 0.05). The levels of SREBP-1c were lower in CG, BJ, and BJB groups than those in MG, SI, BJSI, and BJBSI groups (P < 0.05). The biochemical indexes SOD, GSH, and HDL-c were improved from CG to BJB group (P < 0.05). Inversely, the levels of AST and ALT, TG, TC, LDL-c, and MDA were decreased from CG to BJB group (P < 0.05). These changes enhance antioxidative capability and biochemical index of rats. Blueberry juice and bifidobacteria improve NAFLD by activating SIRTI-mediating signaling pathway.